Detachable fan hub and blades structure



Sept. 25, 1951 D DETACHABLE FAN HUB AND BLADES STRUCTURE .Filed May 5,1949 ml 2 Y N IA/ m a? K n Patented Sept. 25,1951

j UNITED srArss .PATENT OFFICE I 'DETACI-IAB-LE FAN HUB AND BLADESSTRUCTURE- Khattar Ead, Brooklyn, N. YQ Application May'3, 1949, SerialNo. 91,055

My invention relates to air circulating fans, the principal objectthereof being to provide a fan having resilient blades and being adaptedto be attached easily, quickly, and without the use of any tools as wellas without the application of any considerable amount of skill to apiece of lineshafting, to the armature of an electric motor, or thelike, to ventilate and circulate air in any place where machines arelocated and are driven by shafting. The invention applies particularlyto power driven sewing machines located in garment workrooms which arefrequently poorly ventilated.

Another object of the present invention is the provision of a device ofthe character described which consists entirely of soft, bendablematerial, thus eliminating the danger of injury or damage by therotating, unprotected fan, which could occur if the fan were madepartially or entirely of metal or of any other-hard material.

Still another object of the present invention is the provision of adevice of the character described which will adjust the pitch of the fanblades automatically to an angle to the axis of rotation of the fan inaccordance with the speed of rotation, so as to attain always anefiicient pitch and a substantial flow of air irrespective of the numberof revolutions per minute carried out by the axis.

A further object of the present invention is the provision of a deviceof the character described which will fit shafts of various diameters,so that only one size of fan has to be manufactured for a large numberof shaft sizes.

Still a further object of the present invention is the provision of adevice of the character described which is comparatively light inweight, and of a very simple construction, so that it can bemanufactured and sold at a very reasonable price.

With the foregoing and other objects in view which will appear as thedescription proceeds, the invention consists of certain novel details ofconstruction and combinations of parts hereinafter more fully describedand pointed out in the claims, it being understood that changes may bemade in the construction and arrangement of parts without departing fromthe spirit of the invention as claimed.

In the accompanying drawings the preferred forms of the invention havebeen shown.

In said drawings:

Figure 1 is a side elevation, partially shown in vertical section, of apreferred embodiment of my invention; and

2Claims. (cilia-1913):... 1.

Fig. 2 is a front view of the same.

Similar reference characters refer to similar parts throughout theseveral views.

In the drawing the numeral I denotes a cylindrical body of bendablematerial having an open longitudinal section 4 which extends over itsentire length. Two or more fan blades 2 of bendable material radiatefrom the center portion of the body I, and are made as a unit therewithas shown, or are secured thereto by vulcanizing or in any other suitablemanner. The material of which the parts I and 2 are made is eitherrubber or resilient plastic material or any other bendable andpreferably soft substance. Thus one and the same body I can be attachedto shafts of different diameters or even to shafts which are square,triangular, rectangular, polygonal or otherwise shaped in cross-section.The end portions of the body I have at their outer side annular grooves3, which are engaged by straps 5 having buckles 6 at one end andperforations in the opposite end I, or by endless rubber bands or straps(not shown), or the like, for securing the body I to a shaft 8.

While the grooves 3 and the straps 5 can be close to the blades 2, sothat the body I may be comparatively short, I have found that acomparatively long body I of rubber or other elastic material with thestraps at its ends will result in an automatic adjustment of the pitchof the fan blades in accordance with the speed of rotation of the shaft8. If the latter rotates at a low speed, the center portion of theelastic body I rests firmly on the periphery of the shaft 8, while-uponan increase of the speed-the centrifugal forces will create a tensionwhich widens the diameter of the center portion of body I thusdecreasing the angle of the fan blades to the axis of rotation.

Since certain changes may be made in the above article and differentembodiments of the invention could be made without departing from thescope thereof, it is intended that all matter contained in the abovedescription or shown in the accompanying drawing shall be interpreted asillustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which as amatter of language might be said to fall therebetween.

Having thus fully described my said invention, what I claim as new anddesire to secure by Letters Patent in the United States is:

1. A detachable fan hub and blades structure comprising a cylindricallongitudinal body of resilient material having an open longitudinalsection which extends over its entire length and being provided at itsouter side with annular grooves, fan blades made as a unit with saidbody radiating from a portion thereof which is located between saidgrooves, and straps engaging said grooves and being adapted for securingsaid body-to-a shaft.

2. A device of the character described comprising a longitudinalcylindrical body of bend-v able material having an open longitudinalsection which extends over its entire length and provided with annulargrooves at the outer sides of its end portions, bendable portions-shapedas fan blades radiating from the portioning said body, and strapsengaging said grooves and being adapted for firmly securing said body to4 REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 335,640 Simmons Feb. 9, 1886750,904 Smith Feb. 2, 1904 8291. e ew 190'! 1,360,516 Franseen Nov, 30,1920 2,035,081 Lower Mar. 24, 1936 2,040,504 Siegel May 12, 19362,144,326, Callaghan Jan. 17, 1939 2,144,860 Thorp Jan. 24, 19392,212,072 Newnham Aug. 20; 1940 2390,299 Gutkin Dec. 4, 1945 2,461,965lgal ikow Feb. 15, 1949

